pgtable.h 15 KB

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  1. #ifndef _ASM_X86_PGTABLE_H
  2. #define _ASM_X86_PGTABLE_H
  3. #define FIRST_USER_ADDRESS 0
  4. #define _PAGE_BIT_PRESENT 0 /* is present */
  5. #define _PAGE_BIT_RW 1 /* writeable */
  6. #define _PAGE_BIT_USER 2 /* userspace addressable */
  7. #define _PAGE_BIT_PWT 3 /* page write through */
  8. #define _PAGE_BIT_PCD 4 /* page cache disabled */
  9. #define _PAGE_BIT_ACCESSED 5 /* was accessed (raised by CPU) */
  10. #define _PAGE_BIT_DIRTY 6 /* was written to (raised by CPU) */
  11. #define _PAGE_BIT_FILE 6
  12. #define _PAGE_BIT_PSE 7 /* 4 MB (or 2MB) page */
  13. #define _PAGE_BIT_PAT 7 /* on 4KB pages */
  14. #define _PAGE_BIT_GLOBAL 8 /* Global TLB entry PPro+ */
  15. #define _PAGE_BIT_UNUSED1 9 /* available for programmer */
  16. #define _PAGE_BIT_UNUSED2 10
  17. #define _PAGE_BIT_UNUSED3 11
  18. #define _PAGE_BIT_PAT_LARGE 12 /* On 2MB or 1GB pages */
  19. #define _PAGE_BIT_NX 63 /* No execute: only valid after cpuid check */
  20. #define _PAGE_PRESENT (_AT(pteval_t, 1) << _PAGE_BIT_PRESENT)
  21. #define _PAGE_RW (_AT(pteval_t, 1) << _PAGE_BIT_RW)
  22. #define _PAGE_USER (_AT(pteval_t, 1) << _PAGE_BIT_USER)
  23. #define _PAGE_PWT (_AT(pteval_t, 1) << _PAGE_BIT_PWT)
  24. #define _PAGE_PCD (_AT(pteval_t, 1) << _PAGE_BIT_PCD)
  25. #define _PAGE_ACCESSED (_AT(pteval_t, 1) << _PAGE_BIT_ACCESSED)
  26. #define _PAGE_DIRTY (_AT(pteval_t, 1) << _PAGE_BIT_DIRTY)
  27. #define _PAGE_PSE (_AT(pteval_t, 1) << _PAGE_BIT_PSE)
  28. #define _PAGE_GLOBAL (_AT(pteval_t, 1) << _PAGE_BIT_GLOBAL)
  29. #define _PAGE_UNUSED1 (_AT(pteval_t, 1) << _PAGE_BIT_UNUSED1)
  30. #define _PAGE_UNUSED2 (_AT(pteval_t, 1) << _PAGE_BIT_UNUSED2)
  31. #define _PAGE_UNUSED3 (_AT(pteval_t, 1) << _PAGE_BIT_UNUSED3)
  32. #define _PAGE_PAT (_AT(pteval_t, 1) << _PAGE_BIT_PAT)
  33. #define _PAGE_PAT_LARGE (_AT(pteval_t, 1) << _PAGE_BIT_PAT_LARGE)
  34. #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
  35. #define _PAGE_NX (_AT(pteval_t, 1) << _PAGE_BIT_NX)
  36. #else
  37. #define _PAGE_NX (_AT(pteval_t, 0))
  38. #endif
  39. /* If _PAGE_PRESENT is clear, we use these: */
  40. #define _PAGE_FILE _PAGE_DIRTY /* nonlinear file mapping,
  41. * saved PTE; unset:swap */
  42. #define _PAGE_PROTNONE _PAGE_PSE /* if the user mapped it with PROT_NONE;
  43. pte_present gives true */
  44. #define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | \
  45. _PAGE_ACCESSED | _PAGE_DIRTY)
  46. #define _KERNPG_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | \
  47. _PAGE_DIRTY)
  48. /* Set of bits not changed in pte_modify */
  49. #define _PAGE_CHG_MASK (PTE_MASK | _PAGE_PCD | _PAGE_PWT | \
  50. _PAGE_ACCESSED | _PAGE_DIRTY)
  51. #define _PAGE_CACHE_MASK (_PAGE_PCD | _PAGE_PWT)
  52. #define _PAGE_CACHE_WB (0)
  53. #define _PAGE_CACHE_WC (_PAGE_PWT)
  54. #define _PAGE_CACHE_UC_MINUS (_PAGE_PCD)
  55. #define _PAGE_CACHE_UC (_PAGE_PCD | _PAGE_PWT)
  56. #define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
  57. #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | \
  58. _PAGE_ACCESSED | _PAGE_NX)
  59. #define PAGE_SHARED_EXEC __pgprot(_PAGE_PRESENT | _PAGE_RW | \
  60. _PAGE_USER | _PAGE_ACCESSED)
  61. #define PAGE_COPY_NOEXEC __pgprot(_PAGE_PRESENT | _PAGE_USER | \
  62. _PAGE_ACCESSED | _PAGE_NX)
  63. #define PAGE_COPY_EXEC __pgprot(_PAGE_PRESENT | _PAGE_USER | \
  64. _PAGE_ACCESSED)
  65. #define PAGE_COPY PAGE_COPY_NOEXEC
  66. #define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | \
  67. _PAGE_ACCESSED | _PAGE_NX)
  68. #define PAGE_READONLY_EXEC __pgprot(_PAGE_PRESENT | _PAGE_USER | \
  69. _PAGE_ACCESSED)
  70. #define __PAGE_KERNEL_EXEC \
  71. (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_GLOBAL)
  72. #define __PAGE_KERNEL (__PAGE_KERNEL_EXEC | _PAGE_NX)
  73. #define __PAGE_KERNEL_RO (__PAGE_KERNEL & ~_PAGE_RW)
  74. #define __PAGE_KERNEL_RX (__PAGE_KERNEL_EXEC & ~_PAGE_RW)
  75. #define __PAGE_KERNEL_EXEC_NOCACHE (__PAGE_KERNEL_EXEC | _PAGE_PCD | _PAGE_PWT)
  76. #define __PAGE_KERNEL_WC (__PAGE_KERNEL | _PAGE_CACHE_WC)
  77. #define __PAGE_KERNEL_NOCACHE (__PAGE_KERNEL | _PAGE_PCD | _PAGE_PWT)
  78. #define __PAGE_KERNEL_UC_MINUS (__PAGE_KERNEL | _PAGE_PCD)
  79. #define __PAGE_KERNEL_VSYSCALL (__PAGE_KERNEL_RX | _PAGE_USER)
  80. #define __PAGE_KERNEL_VSYSCALL_NOCACHE (__PAGE_KERNEL_VSYSCALL | _PAGE_PCD | _PAGE_PWT)
  81. #define __PAGE_KERNEL_LARGE (__PAGE_KERNEL | _PAGE_PSE)
  82. #define __PAGE_KERNEL_LARGE_NOCACHE (__PAGE_KERNEL | _PAGE_CACHE_UC | _PAGE_PSE)
  83. #define __PAGE_KERNEL_LARGE_EXEC (__PAGE_KERNEL_EXEC | _PAGE_PSE)
  84. #define PAGE_KERNEL __pgprot(__PAGE_KERNEL)
  85. #define PAGE_KERNEL_RO __pgprot(__PAGE_KERNEL_RO)
  86. #define PAGE_KERNEL_EXEC __pgprot(__PAGE_KERNEL_EXEC)
  87. #define PAGE_KERNEL_RX __pgprot(__PAGE_KERNEL_RX)
  88. #define PAGE_KERNEL_WC __pgprot(__PAGE_KERNEL_WC)
  89. #define PAGE_KERNEL_NOCACHE __pgprot(__PAGE_KERNEL_NOCACHE)
  90. #define PAGE_KERNEL_UC_MINUS __pgprot(__PAGE_KERNEL_UC_MINUS)
  91. #define PAGE_KERNEL_EXEC_NOCACHE __pgprot(__PAGE_KERNEL_EXEC_NOCACHE)
  92. #define PAGE_KERNEL_LARGE __pgprot(__PAGE_KERNEL_LARGE)
  93. #define PAGE_KERNEL_LARGE_NOCACHE __pgprot(__PAGE_KERNEL_LARGE_NOCACHE)
  94. #define PAGE_KERNEL_LARGE_EXEC __pgprot(__PAGE_KERNEL_LARGE_EXEC)
  95. #define PAGE_KERNEL_VSYSCALL __pgprot(__PAGE_KERNEL_VSYSCALL)
  96. #define PAGE_KERNEL_VSYSCALL_NOCACHE __pgprot(__PAGE_KERNEL_VSYSCALL_NOCACHE)
  97. /* xwr */
  98. #define __P000 PAGE_NONE
  99. #define __P001 PAGE_READONLY
  100. #define __P010 PAGE_COPY
  101. #define __P011 PAGE_COPY
  102. #define __P100 PAGE_READONLY_EXEC
  103. #define __P101 PAGE_READONLY_EXEC
  104. #define __P110 PAGE_COPY_EXEC
  105. #define __P111 PAGE_COPY_EXEC
  106. #define __S000 PAGE_NONE
  107. #define __S001 PAGE_READONLY
  108. #define __S010 PAGE_SHARED
  109. #define __S011 PAGE_SHARED
  110. #define __S100 PAGE_READONLY_EXEC
  111. #define __S101 PAGE_READONLY_EXEC
  112. #define __S110 PAGE_SHARED_EXEC
  113. #define __S111 PAGE_SHARED_EXEC
  114. #ifndef __ASSEMBLY__
  115. /*
  116. * ZERO_PAGE is a global shared page that is always zero: used
  117. * for zero-mapped memory areas etc..
  118. */
  119. extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
  120. #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
  121. extern spinlock_t pgd_lock;
  122. extern struct list_head pgd_list;
  123. /*
  124. * The following only work if pte_present() is true.
  125. * Undefined behaviour if not..
  126. */
  127. static inline int pte_dirty(pte_t pte)
  128. {
  129. return pte_flags(pte) & _PAGE_DIRTY;
  130. }
  131. static inline int pte_young(pte_t pte)
  132. {
  133. return pte_flags(pte) & _PAGE_ACCESSED;
  134. }
  135. static inline int pte_write(pte_t pte)
  136. {
  137. return pte_flags(pte) & _PAGE_RW;
  138. }
  139. static inline int pte_file(pte_t pte)
  140. {
  141. return pte_flags(pte) & _PAGE_FILE;
  142. }
  143. static inline int pte_huge(pte_t pte)
  144. {
  145. return pte_flags(pte) & _PAGE_PSE;
  146. }
  147. static inline int pte_global(pte_t pte)
  148. {
  149. return pte_flags(pte) & _PAGE_GLOBAL;
  150. }
  151. static inline int pte_exec(pte_t pte)
  152. {
  153. return !(pte_flags(pte) & _PAGE_NX);
  154. }
  155. static inline int pte_special(pte_t pte)
  156. {
  157. return 0;
  158. }
  159. static inline int pmd_large(pmd_t pte)
  160. {
  161. return (pmd_val(pte) & (_PAGE_PSE | _PAGE_PRESENT)) ==
  162. (_PAGE_PSE | _PAGE_PRESENT);
  163. }
  164. static inline pte_t pte_mkclean(pte_t pte)
  165. {
  166. return __pte(pte_val(pte) & ~_PAGE_DIRTY);
  167. }
  168. static inline pte_t pte_mkold(pte_t pte)
  169. {
  170. return __pte(pte_val(pte) & ~_PAGE_ACCESSED);
  171. }
  172. static inline pte_t pte_wrprotect(pte_t pte)
  173. {
  174. return __pte(pte_val(pte) & ~_PAGE_RW);
  175. }
  176. static inline pte_t pte_mkexec(pte_t pte)
  177. {
  178. return __pte(pte_val(pte) & ~_PAGE_NX);
  179. }
  180. static inline pte_t pte_mkdirty(pte_t pte)
  181. {
  182. return __pte(pte_val(pte) | _PAGE_DIRTY);
  183. }
  184. static inline pte_t pte_mkyoung(pte_t pte)
  185. {
  186. return __pte(pte_val(pte) | _PAGE_ACCESSED);
  187. }
  188. static inline pte_t pte_mkwrite(pte_t pte)
  189. {
  190. return __pte(pte_val(pte) | _PAGE_RW);
  191. }
  192. static inline pte_t pte_mkhuge(pte_t pte)
  193. {
  194. return __pte(pte_val(pte) | _PAGE_PSE);
  195. }
  196. static inline pte_t pte_clrhuge(pte_t pte)
  197. {
  198. return __pte(pte_val(pte) & ~_PAGE_PSE);
  199. }
  200. static inline pte_t pte_mkglobal(pte_t pte)
  201. {
  202. return __pte(pte_val(pte) | _PAGE_GLOBAL);
  203. }
  204. static inline pte_t pte_clrglobal(pte_t pte)
  205. {
  206. return __pte(pte_val(pte) & ~_PAGE_GLOBAL);
  207. }
  208. static inline pte_t pte_mkspecial(pte_t pte)
  209. {
  210. return pte;
  211. }
  212. extern pteval_t __supported_pte_mask;
  213. static inline pte_t pfn_pte(unsigned long page_nr, pgprot_t pgprot)
  214. {
  215. return __pte((((phys_addr_t)page_nr << PAGE_SHIFT) |
  216. pgprot_val(pgprot)) & __supported_pte_mask);
  217. }
  218. static inline pmd_t pfn_pmd(unsigned long page_nr, pgprot_t pgprot)
  219. {
  220. return __pmd((((phys_addr_t)page_nr << PAGE_SHIFT) |
  221. pgprot_val(pgprot)) & __supported_pte_mask);
  222. }
  223. static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
  224. {
  225. pteval_t val = pte_val(pte);
  226. /*
  227. * Chop off the NX bit (if present), and add the NX portion of
  228. * the newprot (if present):
  229. */
  230. val &= _PAGE_CHG_MASK;
  231. val |= pgprot_val(newprot) & (~_PAGE_CHG_MASK) & __supported_pte_mask;
  232. return __pte(val);
  233. }
  234. /* mprotect needs to preserve PAT bits when updating vm_page_prot */
  235. #define pgprot_modify pgprot_modify
  236. static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot)
  237. {
  238. pgprotval_t preservebits = pgprot_val(oldprot) & _PAGE_CHG_MASK;
  239. pgprotval_t addbits = pgprot_val(newprot);
  240. return __pgprot(preservebits | addbits);
  241. }
  242. #define pte_pgprot(x) __pgprot(pte_flags(x) & ~PTE_MASK)
  243. #define canon_pgprot(p) __pgprot(pgprot_val(p) & __supported_pte_mask)
  244. #ifndef __ASSEMBLY__
  245. #define __HAVE_PHYS_MEM_ACCESS_PROT
  246. struct file;
  247. pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
  248. unsigned long size, pgprot_t vma_prot);
  249. int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
  250. unsigned long size, pgprot_t *vma_prot);
  251. #endif
  252. /* Install a pte for a particular vaddr in kernel space. */
  253. void set_pte_vaddr(unsigned long vaddr, pte_t pte);
  254. #ifdef CONFIG_PARAVIRT
  255. #include <asm/paravirt.h>
  256. #else /* !CONFIG_PARAVIRT */
  257. #define set_pte(ptep, pte) native_set_pte(ptep, pte)
  258. #define set_pte_at(mm, addr, ptep, pte) native_set_pte_at(mm, addr, ptep, pte)
  259. #define set_pte_present(mm, addr, ptep, pte) \
  260. native_set_pte_present(mm, addr, ptep, pte)
  261. #define set_pte_atomic(ptep, pte) \
  262. native_set_pte_atomic(ptep, pte)
  263. #define set_pmd(pmdp, pmd) native_set_pmd(pmdp, pmd)
  264. #ifndef __PAGETABLE_PUD_FOLDED
  265. #define set_pgd(pgdp, pgd) native_set_pgd(pgdp, pgd)
  266. #define pgd_clear(pgd) native_pgd_clear(pgd)
  267. #endif
  268. #ifndef set_pud
  269. # define set_pud(pudp, pud) native_set_pud(pudp, pud)
  270. #endif
  271. #ifndef __PAGETABLE_PMD_FOLDED
  272. #define pud_clear(pud) native_pud_clear(pud)
  273. #endif
  274. #define pte_clear(mm, addr, ptep) native_pte_clear(mm, addr, ptep)
  275. #define pmd_clear(pmd) native_pmd_clear(pmd)
  276. #define pte_update(mm, addr, ptep) do { } while (0)
  277. #define pte_update_defer(mm, addr, ptep) do { } while (0)
  278. #endif /* CONFIG_PARAVIRT */
  279. #endif /* __ASSEMBLY__ */
  280. #ifdef CONFIG_X86_32
  281. # include "pgtable_32.h"
  282. #else
  283. # include "pgtable_64.h"
  284. #endif
  285. /*
  286. * the pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
  287. *
  288. * this macro returns the index of the entry in the pgd page which would
  289. * control the given virtual address
  290. */
  291. #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
  292. /*
  293. * pgd_offset() returns a (pgd_t *)
  294. * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
  295. */
  296. #define pgd_offset(mm, address) ((mm)->pgd + pgd_index((address)))
  297. /*
  298. * a shortcut which implies the use of the kernel's pgd, instead
  299. * of a process's
  300. */
  301. #define pgd_offset_k(address) pgd_offset(&init_mm, (address))
  302. #define KERNEL_PGD_BOUNDARY pgd_index(PAGE_OFFSET)
  303. #define KERNEL_PGD_PTRS (PTRS_PER_PGD - KERNEL_PGD_BOUNDARY)
  304. #ifndef __ASSEMBLY__
  305. enum {
  306. PG_LEVEL_NONE,
  307. PG_LEVEL_4K,
  308. PG_LEVEL_2M,
  309. PG_LEVEL_1G,
  310. PG_LEVEL_NUM
  311. };
  312. #ifdef CONFIG_PROC_FS
  313. extern void update_page_count(int level, unsigned long pages);
  314. #else
  315. static inline void update_page_count(int level, unsigned long pages) { }
  316. #endif
  317. /*
  318. * Helper function that returns the kernel pagetable entry controlling
  319. * the virtual address 'address'. NULL means no pagetable entry present.
  320. * NOTE: the return type is pte_t but if the pmd is PSE then we return it
  321. * as a pte too.
  322. */
  323. extern pte_t *lookup_address(unsigned long address, unsigned int *level);
  324. /* local pte updates need not use xchg for locking */
  325. static inline pte_t native_local_ptep_get_and_clear(pte_t *ptep)
  326. {
  327. pte_t res = *ptep;
  328. /* Pure native function needs no input for mm, addr */
  329. native_pte_clear(NULL, 0, ptep);
  330. return res;
  331. }
  332. static inline void native_set_pte_at(struct mm_struct *mm, unsigned long addr,
  333. pte_t *ptep , pte_t pte)
  334. {
  335. native_set_pte(ptep, pte);
  336. }
  337. #ifndef CONFIG_PARAVIRT
  338. /*
  339. * Rules for using pte_update - it must be called after any PTE update which
  340. * has not been done using the set_pte / clear_pte interfaces. It is used by
  341. * shadow mode hypervisors to resynchronize the shadow page tables. Kernel PTE
  342. * updates should either be sets, clears, or set_pte_atomic for P->P
  343. * transitions, which means this hook should only be called for user PTEs.
  344. * This hook implies a P->P protection or access change has taken place, which
  345. * requires a subsequent TLB flush. The notification can optionally be delayed
  346. * until the TLB flush event by using the pte_update_defer form of the
  347. * interface, but care must be taken to assure that the flush happens while
  348. * still holding the same page table lock so that the shadow and primary pages
  349. * do not become out of sync on SMP.
  350. */
  351. #define pte_update(mm, addr, ptep) do { } while (0)
  352. #define pte_update_defer(mm, addr, ptep) do { } while (0)
  353. #endif
  354. /*
  355. * We only update the dirty/accessed state if we set
  356. * the dirty bit by hand in the kernel, since the hardware
  357. * will do the accessed bit for us, and we don't want to
  358. * race with other CPU's that might be updating the dirty
  359. * bit at the same time.
  360. */
  361. struct vm_area_struct;
  362. #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
  363. extern int ptep_set_access_flags(struct vm_area_struct *vma,
  364. unsigned long address, pte_t *ptep,
  365. pte_t entry, int dirty);
  366. #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
  367. extern int ptep_test_and_clear_young(struct vm_area_struct *vma,
  368. unsigned long addr, pte_t *ptep);
  369. #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
  370. extern int ptep_clear_flush_young(struct vm_area_struct *vma,
  371. unsigned long address, pte_t *ptep);
  372. #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
  373. static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
  374. pte_t *ptep)
  375. {
  376. pte_t pte = native_ptep_get_and_clear(ptep);
  377. pte_update(mm, addr, ptep);
  378. return pte;
  379. }
  380. #define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
  381. static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
  382. unsigned long addr, pte_t *ptep,
  383. int full)
  384. {
  385. pte_t pte;
  386. if (full) {
  387. /*
  388. * Full address destruction in progress; paravirt does not
  389. * care about updates and native needs no locking
  390. */
  391. pte = native_local_ptep_get_and_clear(ptep);
  392. } else {
  393. pte = ptep_get_and_clear(mm, addr, ptep);
  394. }
  395. return pte;
  396. }
  397. #define __HAVE_ARCH_PTEP_SET_WRPROTECT
  398. static inline void ptep_set_wrprotect(struct mm_struct *mm,
  399. unsigned long addr, pte_t *ptep)
  400. {
  401. clear_bit(_PAGE_BIT_RW, (unsigned long *)&ptep->pte);
  402. pte_update(mm, addr, ptep);
  403. }
  404. /*
  405. * clone_pgd_range(pgd_t *dst, pgd_t *src, int count);
  406. *
  407. * dst - pointer to pgd range anwhere on a pgd page
  408. * src - ""
  409. * count - the number of pgds to copy.
  410. *
  411. * dst and src can be on the same page, but the range must not overlap,
  412. * and must not cross a page boundary.
  413. */
  414. static inline void clone_pgd_range(pgd_t *dst, pgd_t *src, int count)
  415. {
  416. memcpy(dst, src, count * sizeof(pgd_t));
  417. }
  418. #include <asm-generic/pgtable.h>
  419. #endif /* __ASSEMBLY__ */
  420. #endif /* _ASM_X86_PGTABLE_H */